Check both sides of your engine to make sure that they have head gaskets....
Read on one of the other forums that a new Mustang owner took his Mustang in because he was having to add water on a regular basis. Dealer put the Mustang up on the rack, got it warmed up, then noticed that there was water seeping out from around the head. Tore the head off and there was no gasket on that side. Their response was, "Well, a few of them got out this way."
Needless to say, it's an easy check from the outside of the engine, especially if you just got a new one in a crate.
All of my engines do come with head gaskets on both sides.
